COVER FOR A SEALING RING OF AN EARMUFF

Abstract: Use of a superabsorbent nonwoven material in a moisture absorbing cover for an earmuff. A moisture absorbing ring-shaped cover for a sealing ring of an earmuff includes an inner layer (23) of super-absorbent fibre material. A device for use in moisture absorption at an earmuff comprises a cover (7) of this type and a supplementary cover (9) of the same construction intended for application within the earmuff and with a form corresponding to that of the area encompassed by the ring-shape cover (7).

Description: COVER FOR A SEALING RING OF AN EARMUFF The present invention relates to a moisture absorbing cover for an earmuff. The invention accordingly relates to a cover for a sealing ring of an earmuff, which sealing ring, after application of the earmuff over a person's ear, is intended to abut the person's head around the ear. The invention also relates to a device for use in moisture absorption in connection with an earmuff, which includes a cover of the above type and additionally a supplementary cover. Finally, the invention relates to use of a special material in a moisture absorbing cover for an earmuff. Persons who protractedly wear earmuffs, such as hearing protecting muffs and/or communication headsets, are often troubled by sweat and moisture at the sealing rings and within the ear spaces of the earmuffs. There have been attempts to resolve this problem by attaching exchangable layers of absorbent paper material to the sealing rings of earmuffs. In practice, however, this solution has not been found to give satisfactory results. The object of the present invention is to provide an improved solution to the abovementioned moisture problems while using a moisture absorbing cover. In accordance with the invention, this object is attained by a cover, a device and a use which bear the features indicated in the accompanying patent claims. The invention is thus based on an insight that using a "superabsorbent" material in a moisture absorbing cover which is applied to an earmuff provides significant advantages. Over and above that such material has proven to provide extremely good moisture absorbance in this context, the material has proven to have the capacity to take up and retain moisture even under the present comparatively high pressure forces which are necessitated by the fact that the sealing ring of an earmuff must abut the person's head with a not insignificant force to obtain the desired sealing effect. The superabsorbent material is preferably incorporated in an inner layer of the cover. With the aim of providing the wearer of the earmuff with a feeling of dryness and to ensure good moisture uptake, the cover should have an outer layer having a high moisture permeability or mois¬ ture transport effect so that the moisture is effectively conveyed thereby into the inner layer which contains the superabsorbent material. The superabsorbent material is advantageously a fibrous material, preferably included in a nonwoven or bonded- fibre fabric layer. A layer of this sort, aside from the superabsorbent fibres, may include other fibres which provide stability and strength and which, in cooperation with similar fibres in optional enclosing other layers, may provide a cohesive and reinforcing efect. Such other fibres may be hydrophilic or wetting agent-treated fibres and/or staple fibres, "staple fibres" being used in a broad sense and not being limited, for example, to cut fibres. The superabsorbent material is advantageously polyacrylate based. Advantageously, the cover has an outer layer, an inner layer and a rear or backing layer, each of which is a nonwoven or bonded-fibre fabric layer. The preferred layer configurations and compositions, not least to provide good mechanical properties at a low cost, are apparent in the dependent patent claims. In accordance with a further aspect of the invention, a cover of the sort under discussion may also be applied onto an earmuff at a location other than its sealing ring, namely within the ear space of the earmuff, whereby additionally improved moisture uptake is obtained. To this end, an extra, separate cover may be advantageously used, which is complementary to a ring-shaped cover intended for the sealing ring itself. The complementary cover, in other words, preferably has a configuration corresponding to the area which is encompassed by the ring-shaped cover, i.e. a configuration which also corresponds to the opening of the earmuff into the ear space. A preferred embodiment of a device in accordance with the invention for use in moisture absorption in connection with an earmuff, comprises a first ring-shaped cover and a second cover complementary thereto, both covers being stamped out simultaneously, though separated from each other, from a flat web of material and releasably secured to a carrier by means of an adhesive attached to the rear side of the covers and intended for attachment onto the earmuff. It will be appreciated that such devices can be simply manufactured and handled before application onto an ear- muff, either individually or placed in an appropriate number on a suitable carrier, for example in the form of a sheet or a continuous band. The invention will now be described in greater detail in relation to an exemplary embodiment and with reference to the accompanying drawings, in which: Fig. 1 is a schematic plan view of an embodiment of a device in accordance with the invention; Fig. 2 is a schematic perspective view illustrating covers in accordance with the invention derived from a device in accordance with Fig. 1; and Fig. 3 is a schematic partial exploded view illustrating a section along III-III in Fig. 2. The device of Fig. 1 comprises two flat cover sets 1 and 3 supported on a sheet-like, specially treated rectangular carrier 5. Each set 1 and 3 includes a first ring-shaped cover 7 and a second cover 9 surrounded thereby. The form of the ring-shaped cover 7 corresponds to a conventional sealing ring (not shown) of an earmuff, on which the cover is intended to be applied. The second cover 9 completely fills out the area within the cover 7 and is at least in all essential respects separated from the latter by a stamped line 11. The covers 7 and 9 are stamped out in common from a continuous web of material. Both of the covers 7 and 9 therefore have the same construction, as is explained in more detail in connection with Fig. 3. The covers are releasably secured to the carrier 5 specially prepared therefor, by means of streaks of glue attached to their rear sides, which glue is also intended for securing the covers to an earmuff. During application, the covers 7 and 9 are lifted away from the carrier 5 and applied to an earmuff, the ring- shaped cover on the sealing ring of the earmuff and the second cover within the earmuff, for example on the expanded plastic insulating material which is most often located therein. As will be appreciated, the second cover has a form which is adapted to the opening into the interior of the earmuff. If the covers 7,9 are completely separated from each other, they can be easily taken up and applied one at a time; compare also Fig. 2. If the covers are in all essential respects separated from each other but can nevertheless be handled as a unit upon lifting from the carier 5, said unit can be applied to the earmuff firstly with the cover 7 over the sealing ring, after which the inner, second cover 9, while being released from the ring-shaped cover 7, is simply pushed into, and secured within, the earmuff. Fig. 3 illustrates the construction of the material from which the covers 7 and 9 are prepared. The material includes an outer layer 21, an inner layer 23 and a backing layer 25, on the latter of which the streaks of glue are attached. The surface layer 21 and the backing layer 25 are thin, impermeable layers consisting of around 25% hydrophilic cellulose fibres and around 75% staple fibres of the Bi component PP/PE type. The inner layer 23 consists of around 15% "FSA" superabsorbent fibres which are polyacrylate based, around 65% hydrophilic cellulose fibres and around 20% staple fibres of the same type as in both of the other layers. Said superabsorbent fibres are a product developed by Allied Colloids Ltd. and Courtaulds Ltd. The material is the form of a nonwoven web in which the staple fibres of the same type in the layers provide a cohesive and reinforcing effect.

Claims: CLAIMS 1. A cover (7) for the sealing ring of an earmuff, which sealing ring, upon application of the earmuff over a person's ear, is intended to abut the person's head around the ear, characterized in that it comprises an inner moisture absorbing layer (23) which includes a "superabsorbent" material. 2. A cover (7) according to claim 1, characterized in that the inner layer (23) includes superabsorbent fibres. 3. A cover (7) according to claim 2, characterized in that the inner layer (23) is a nonwoven or bonded-fibre fabric. 4. A cover (7) according to any one of the preceding claims, characterized in that the inner layer (23) is made up of a mixture of superabsorbent fibres, hydrophilic fibres, especially cellulose based fibres, and staple fibres. 5. A cover (7) according to any one of the preceding claims, characterized in that the inner layer (23) contains from around 10% to around 20%, preferably around 15%, of "superabsorbent fibres" and is otherwise substantially of hydrophilic fibres, especially cellulose based fibres, typically from around 50% to around 75% and preferably around 65%, and staple fibres. 6. A cover (7) according to any one of the preceding claims, characterized in that it has an outer layer (21) which has high moisture permeability and which is preferably a nonwoven or bonded-fibre fabric including a mixture of hydrophilic fibres, especially cellulose based fibres, and staple fibres. 7. A cover (7) according to any one of the preceding claims, characterized in that it has a backing layer (25) arranged for adhering to the sealing ring of the earmuff, which backing layer is preferably a nonwoven or bonded- -fibre fabric including a mixture of hydrophilic fibres, especially cellulose based fibres, and staple fibres. 8. A cover (7) according to claim 7, characterized in that the outer layer (21), the inner layer (23) and the backing layer (25) to a certain extent include the same sort of fibres which provide a cohesive and reinforcing effect. 9. A cover (7) according to any one of claims 6 to 8, characterized in that the outer layer (21) and the backing layer (25) have from around 20% to around 30%, preferably around 25% hydrophilic fibres and are otherwise of staple fibres. 10. A cover (7) according to any one of claims 4 to 9, characterized in that the staple fibres are of the Bi component PP/PE type. 11. A device for moisture absorption at an earmuff, characterized in that it includes a first ring-shaped cover (7) in accordance with any one of claims 1 to 10, which is intended to be placed on a sealing ring of the earmuff, and a supplementary second cover (9) whose configuration corresponds to that of the area encompassed by the first cover (7) and which is intended to be located within the earmuff inside the sealing ring and which has the same construction as the first cover. 12. A device according to claim 11, characterized in that said first and second covers (7, 9) are stamped out together from a flat web of material and are releasably secured to a carrier (5) by means of adhesive means (13) attached to the rear side of the covers and intended for securing to the earmuff. 13. Use of a "superabsorbent" material, preferably in fibrous form, especially incorporated in a nonwoven or bonded-fibre fabric layer, in a moisture absorbing cover for a sealing ring of an earmuff.

Inventors: ANDERSSON LARS-GUNNAR LENNART, ANDERSSON, LARS-GUNNAR, LENNART
Applicants: ANDERSSON LARS GUNNAR LENNART, BILSOM AB, ANDERSSON, LARS-GUNNAR, LENNART
Application year: 1994
Main classification: A61F11
IPC codes: A61F11, H04R1